1. Field of the Invention
The present invention relates to image forming apparatuses which form a latent image on an image carrier by electrophotography or electrostatic recording, for example, and develop the latent image to acquire a visible image.
2. Description of the Related Art
Some developing apparatuses for use in an electrophotography image forming system may have a development roller being a toner carrier which develops an electrostatic latent image and a supply roller being a toner supply member which rotates in contact with the development roller and supplies toner to the development roller. A general supply roller has a urethane sponge layer on its surface as a foam layer for holding toner to be supplied to the development roller. Japanese Patent Laid-Open No. 2009-009035 discloses an example of the developing apparatus. Japanese Patent Laid-Open No. 2009-009035 describes a contact area of a development roller 1 and a supply roller 2 with an uppermost stream position in the direction of rotation of the supply roller set higher than a lowermost stream position, as illustrated in FIG. 9.